So Bored, So She Passed Out Before Her Nap Time – CO Poisoning

co-001It’s still 1993. You are finishing up your rotation at the Bogota General Hospital in Colombia. It’s your last day. EMS rolls in a 40-year-old female who was found lying down on the floor of her apartment. The patient’s husband had come in and then found his wife minimally responsive. As per husband, his son was also acting “different” and looked confused. The patient does not have any significant past medical history or recent drug exposure. Upon further questioning, the husband tells you that yesterday he bought a new boiler, which he installed it in the basement.


You are suspecting CO poisoning.

What are the symptoms?

Symptoms may range from flu-like symptoms to coma:

-Headache (most common)



-Blurry vision


-Chest pain & cardiac dysrhythmias

-Lightheadedness/dizziness (2nd most common)

-Cutaneous blistering



What is the epidemiology of CO poisoning?

Carbon monoxide (CO) poisoning is responsible for up to 40,000 emergency department (ED) visits and 5000 to 6000 deaths per year. Unlike intentional poisoning, unintended poisoning demonstrates both seasonal and regional variation, and it is most common during the winter months in cold climates

How do you measure CO levels?

CO poisoning can be diagnosed by directly measuring carboxyhemoglobin percentage (COHb). Note that the percentage does not correlate with signs and symptoms.  

You sent patient’s venous blood gas level, and CO level is elevated at 16%.

How do you interpret COHb?

-Nonsmoker living outside of urban area ~ 0.4-1.0%

-Nonsmoker living in an urban area ~ ≤ 5%

-Heavy chronic smoker ~ ≤ 15%

-Mild CO poisoning ~ >10% with no clinical signs and symptoms

-Moderate CO poisoning ~ >10% with clinical signs and symptoms

-Severe CO poisoning ~ > 20% with confusion, altered mental status, loss of consciousness, or signs of cardiac ischemia

You start the patient on oxygen therapy via a non-rebreather oxygen mask. Is this enough? How much oxygen is needed, for how long?

Oxygen administration enhances the elimination of CO from the body by decreasing the elimination CO half-life.

CO half-life

Room Air

4-5 hours

100% O2 by non-rebreather mask

~ 1 hour

Hyperbaric Oxygen

~ 20 minutes

What are indications for hyperbaric oxygen (HBO) therapy?

The Undersea and Hyperbaric Medical Society recommends HBO therapy for patients with any of the following:

-Focal neurological findings

-Severe acidosis


-Acute myocardial infarction

-CO exposure of >24 hours

-Carboxyhemoglobin level > 25%

-Pregnancy w/ carboxyhemoglobin level >15%

*The goal of treatment with hyperbaric oxygen is the prevention of long-term and permanent neurocognitive dysfunction, rather than the enhancement of short-term survival rates. However, the use of hyperbaric oxygen remains controversial, and systematic reviews have highlighted the need for further research to define its role.

What are long term symptoms of CO poisoning (if not adequately treated)?

Delayed neurological sequelae (DNS): Can occur days to weeks after apparent resolution of acute symptoms in up to 46% of patients. Patients can present with progressive dementia, psychosis, motor disturbances, ataxia, and long-term cognitive deficits.

Bonus: What would you expect to find on imaging in patients with long-term CO poisoning?

On MRI, you may see symmetric abnormal signal within the deep gray matter (most commonly the globus pallidus)

The images below show MRI of a patient who presented to emergency department with a 5-month history of progressive dementia. She was initially worked up for different neurological and psychiatric diseases; however, upon further investigation, it was found that 6 months ago her house was burned down.



Thanks to Dr. deSouza, and Dr. Willis.



The post So Bored, So She Passed Out Before Her Nap Time – CO Poisoning appeared first on The Original Kings of County.

Presentation masterclass with Ross Fisher


We’re stoked to finally be able to announce something we’ve been working on for a while: A presentation masterclass featuring none other than Ross Fisher.

Instead of listing all the details here, head on over to the separate event site and have a look:

P³ masterclass

Booking opens today! Hope to see you there!




The post Presentation masterclass with Ross Fisher appeared first on scanFOAM.

The 52 in 52 Review: The HEART score


Article citation: Backus BE, Six AJ, Kelder JC, Bosschaert MA, et al. A prospective validation of the HEART score for chest pain patients at the emergency department. Int J Cardiol. 2013 Oct 3;168(3):2153-8. PMID: 23465250


What we already know about the topic: Chest pain is one of the most common complaints in the ED. However, most chest pain patients have no clear cardiac pathology upon initial presentation. Providers are often forced to postpone decision-making while waiting for serial troponins or by admission to observation. This results in prolonged lengths of stay for patients and contributes to ED crowding.


Why this study is important: In this study, the authors propose a clinical decision rule (i.e. the HEART score) that can potentially help ED providers decide who can be safely discharged after a single negative troponin.


Brief overview of the study: This study is the prospective validation study for the HEART score, which was previously derived in an earlier study by the same authors. This score was designed to be used by ED providers to risk-stratify patients based on history, EKG findings, age, risk factors, and a single troponin. A total of 2,388 patients presenting to one of 10 different EDs with chest pain were included in the study. Only 1.7% of patients with a low HEART score of 0-3 (15/870) had a major adverse cardiac event (MACE) within six weeks. This was less than the predetermined 5% cut-off and so the authors concluded that a low HEART score could safely be used to decide which patients can be discharged early from the ED.


Limitations: Primary issues with this study are: (1) The authors used a cut-off of <5% for major adverse cardiac events. In other words, it’s possible that up to 5% (1 in 20) of patients in the “safe for discharge after a single troponin group” could potentially have a MACE. That risk threshold is much too high for most providers. (2) The study was conducted in the Netherlands in 2,388 likely genetically homogenous Caucasian patients. It’s unclear how well the HEART score would hold up in the multicultural diversity of New York City.


Take home points: Use the HEART score with caution, depending on your risk tolerance and the types of patients that you’re evaluating.

Big Picture Paediatrics : Adverse Childhood Experiences

So much of paediatrics, and medicine in general, is focussed on small experimental or observational studies. This series of posts takes the wider view; we’re talking here about some of the biggest and longest running studies that help us frame, measure and understand childhood through time and across the world.

Who & what was studied?

Kaiser Permanente is a large Medical Insurer in the USA; they collected data in two waves in the primary care setting with a view to describing the long-term relationship of childhood experiences to important medical and public health problems. The study initially rolled out in 1996 & 1997.

Felitti, VJ, Anda RF, Nordenberg D et al. Relationship of Childhood Abuse and Household Dysfunction to Many of the Leading Causes of Death in Adults : The Adverse Childhood Experiences (ACE) Study. American Journal of Preventive Medicine. 1998:14, 245–258.

The study aimed to assess – both retrospectively and prospectively – the long-term impact of abuse and household dysfunction during childhood on disease risk factors and incidence, quality of life, health care utilization, and mortality for adults.

Here is the actual questionnaire:

Answer yes or no; all ACE questions refer to the respondent’s first 18 years of life.


  • Emotional abuse: A parent, stepparent, or adult living in your home swore at you, insulted you, put you down, or acted in a way that made you afraid that you might be physically hurt.
  • Physical abuse: A parent, stepparent, or adult living in your home pushed, grabbed, slapped, threw something at you, or hit you so hard that you had marks or were injured.
  • Sexual abuse: An adult, relative, family friend, or stranger who was at least 5 years older than you ever touched or fondled your body in a sexual way, made you touch his/her body in a sexual way, attempted to have any type of sexual intercourse with you.

Household Challenges

  • Mother treated violently: Your mother or stepmother was pushed, grabbed, slapped, had something thrown at her, kicked, bitten, hit with a fist, hit with something hard, repeatedly hit for over at least a few minutes, or ever threatened or hurt by a knife or gun by your father (or stepfather) or mother’s boyfriend.
  • Household substance abuse: A household member was a problem drinker or alcoholic or a household member used street drugs.
  • Mental illness in household: A household member was depressed or mentally ill or a household member attempted suicide.
  • Parental separation or divorce: Your parents were ever separated or divorced.
  • Criminal household member: A household member went to prison.


  • Emotional neglect: Someone in your family helped you feel important or special, you felt loved, people in your family looked out for each other and felt close to each other, and your family was a source of strength and support.
  • Physical neglect: There was someone to take care of you, protect you, and take you to the doctor if you needed it, you didn’t have enough to eat, your parents were too drunk or too high to take care of you, and you had to wear dirty clothes.

What does this mean?

The ACEs questionnaire accumulates a score from zero to seven based on yes/no responses to the above questions. These results in conjunction with a “Health Appraisal Clinic’s questionnaire” allowed correlation with risk factors such as smoking, severe obesity, physical inactivity, depressed mood, suicide attempts, alcoholism, any drug abuse, sexually transmitted diseases, parental drug abuse and a high lifetime number of sexual partners (>50), as well as the big swingers; mortality and overall morbidity.

The ACE score has been utilised to demonstrate a graded dose-response with more than 40 outcomes. You can see the entire list of publications here.

How good is this dataset?

Although there are almost all of the expected threats to validity from a questionnaire administered to people obtaining health insurance in the USA in the 1990s, the dataset is very good.

Of the 13,494 surveys, there was a 70.5% (9508) response rate, sent a week after standardised medical review. Respondents who did not respond to all questions were excluded from the final analysis. After non-responders and exclusions, a total dataset of 8056 responders was analysed. Alarmingly, more than half of the exclusions were for not answering the question about childhood sexual abuse. This certainly raises some concern for a risk of underreporting, particularly if this was the only question omitted! 

What meaning can be drawn from the results (so far)?

The dataset has lent itself to the associations between adverse childhood experiences and a veritable laundry list of medical, psychiatric pathology as well as social and public health problems.

This is data reports that 1 in 5 were sexually abused, nearly 1 in 4 lived with a “problem drinker or alcoholic” and that around 1 in 6 had a household member who was depressed or mentally ill.

It’s worth remembering that this study paints a picture of the adverse childhood experiences of the older generations in the USA – the mean age of respondents was 56.1 (19-92) years – in a study undertaken just over 20 years ago.

Rather than provide a snapshot of what childhood is like today, this data informs us about the childhood of parents of our patients. This gives us some understanding and frameworks by which to consider expectations of childhood from the parental & societal viewpoint – that most parents hope for a rosier childhood with fewer adverse experiences than their own.

With this in mind, and with a critical eye to some of the correlating outcomes, behaviours such as alcohol & drug abuse, smoking, over-eating, and sexual behaviours might alternatively be viewed as both coping strategies and symptoms of the anxiety, anger and depression that is likely co-morbid with high levels of adverse childhood experiences.

Primary prevention of adverse childhood experiences necessitates change at the societal level; with a focus on improving the quality of family and household environments through the childhood years.

Funding for the original study was combined between Kaiser Permanente (San Diego) and the US Center for Disease Control.

Where next?

The Centre for Disease in Childhood has taken over the study and, since 2009, transformed it into a national program across 32 states of the USA, called “Behavioral Risk Factor Surveillance System” (BRFSS). Data from the 2010 BRFSS has been published and includes more than 50,000 respondents. You can see more about the participating states, future timeline and previous data via the CDC website, here.

Felitti, VJ, Anda RF, Nordenberg D et al. Relationship of Childhood Abuse and Household Dysfunction to Many of the Leading Causes of Death in Adults : The Adverse Childhood Experiences (ACE) Study. American Journal of Preventive Medicine. 1998:14, 245–258. 

Centers for Disease Control and Prevention, National Center for Injury Prevention and Control, Division of Violence Prevention Adverse Childhood Experiences (ACEs)”.U.S. Department of Health & Human Services, Atlanta, USA. Accessed 27 September 2016.

Centers for Disease Control and Prevention, National Center for Injury Prevention and Control, Division of Violence Prevention. “About Behavioral Risk Factor Surveillance System ACE Data”.U.S. Department of Health & Human Services, Atlanta, USA. Accessed 5 October 2016.

Für jeden Tag: Übersetzungs-Apps

Bei der Tätigkeit als Notfallmediziner – ob auf der Straße oder in der Notaufnahme – sind wir beinahe täglich mit Patientinnen oder Patienten konfrontiert, für die Deutsch nicht die Muttersprache ist. Hier in Nürnberg sind neben anglo-amerikanischen Touristen besonders Türkisch, Russisch und Arabisch relevante Fremdsprachen.

Natürlich gibt es Dolmetscher, Angehörige oder Angestellte mit Fremdsprachenkenntnissen, die helfen können – am Klinikum Nürnberg haben wir sogar ein tolles Video-Dolmetsch-System.

Aber – machmal muss es auch schnell gehen oder die Umstände (z.b. in der Patientenwohnung) ermöglichen es nicht, einen Dolmetscher hinzuzuziehen. Hier helfen beispielsweise Apps – und ich möchte Ihnen ein paar der Besten vorstellen:


7,99€ iPhone / 5,99€ Android

Spektakulär gut! Hier merkt man, dass die App für die Notaufnahme und den Rettungsdienst programmiert wurde. Mit konkreten Fragen, Protokoll der Antworten und zahlreichen Sprachen und Audio-Ausgabe. Ein Video mit Infos zur App finden Sie hier.


Universal Doctor Speaker

Aktuell kostenlos für iPhone / Android im Rahmen der Flüchtlingskrise.

Eine sehr gute App mit vielen Sprache und Optionen. Teils nicht immer perfekt für die Notfallmedizin angepasst (einige Fragen fehlen oder sind unklar formuliert).


Weitere Apps: Es gibt zahlreiche “Instant-Übersetzer” Apps, z.b. iTranslate für 4,99€ (iPhone / Android) oder das kostenlose Google Translate (iPhone / Android). Die meisten benötigen aber eine durchgehende Internet-Verbindung für direkt-Übersetzungen und sind im medizinischen Bereich eher schwachbrüstig.

Mein Tipp: Probieren Sie es aus! Die wenigen Euro sind sehr gut investiert!

Klar: Der Einsatz derartiger Apps muss natürlich im Rahmen der rechtlichen Hintergründe erfolgen und kann keinesfalls professionelle Dolmetscher, z.b. für Aufklärungsgespräche ersetzen.